Refrigeration apparatus



R. E. WALLENBROCK REFRIGERATION APPARATUS June 16, 1964 1961 2Sheets-Sheet 1 Filed July 27 June 16, 1964 R WALLENBRQCK 3,137,146

REFRIGERATION APPARATUS v 2 Sheets-Sheet 2 Filed July 27, 1961 IN VENTOR.

United States Patent 3,137,146 REFRIGERATION APRARATUS Ralph E.Wallenbrock, Evansville, Ind., assignor to Whirlpool Corporation, acorporation of Delaware Filed July 27, 1961, Ser. No. 127,343 Claims.(Cl. 62-419) This invention relates to refrigeration apparatus andparticularly to refrigeration apparatus such as chest type freezers. v

In the conventional chest freezers, the means for refrigerating the mainstorage chamber thereof comprises an evaporator means installed in theinsulative wall defining the chamber for withdrawing heat from thechamber through the liner defining the inner element of the wall. Suchan arrangement has a substantial number of disadvantages such asrelatively high cost and the tendency of frost collection on therelatively cold liner surfaces. Recently, frost-free refrigerationapparatuses have been developed wherein means are provided inassociation with the wall mounted evaporator means for causing the frostto migrate from the chamber and liner surfaces to a remote position forsubsequent removal as desired. In one such apparatus, the desiredmigration of the frost is effected by providing an extremely lowtemperature surface at a point spaced from the chamber and means forcirculating air between the chamber and the low temperature surfacewhereby moisture carried by the air deposits on the low temperaturesurface in the form of frost, effectively precluding formation of thefrost in the chamber.

While the latter apparatus has the desirable feature of providing asubstantially frost-free refrigeration chamber,

such as in a chest type freezer, it has the disadvantage of furtherincreasing the relatively high cost of such a freezer wherein theevaporator is installed in the chamber walls.

The present invention comprehends a new and improved refrigerationapparatus which provides desirable frost-free functioning as in the lastdescribedrefrigeration apparatus but in an extremely simple andeconomical manner.

Thus, a principal feature of the present invention is the provision of anew and improved refrigeration apparatus.

Another feature of the invention is'the provision of such refrigerationapparatus arranged to provide subfreezing refrigeration of a chamberwithout the need of evaporator structure installed in the walls definingthe chamber. i

A further feature of the invention is the provision of such arefrigeration apparatus provided with means for effecting a sub-freezingrefrigeration of a freezer chamber solely by circulation of sub-freezingtemperature air therethrough.

Still another feature of the invention is the provision of suchrefrigeration apparatus having new and improved means for effectinguniformly distributed delivery of the sub-freezing air to the freezerchamber.

Still another feature of the invention is the provision of suchrefrigeration apparatus including means defining a chamber, means forproviding refrigerated air under pressure for refrigerating the chamberto a sub-freezing temperature, and means for delivering refrigerated airfrom the providing means through a plurality of inlets to the chamber atsubstantially spaced points therein to refrigerate the chambersubstantially uniformly throughout to said sub-freezing temperature.

Other features and advantages of the invention will be apparent from thefollowing description taken in connection with the accompanying drawingswherein:

FIGURE 1 is a fragmentary vertical longitudinal section of a chestfreezer provided with refrigeration apparatus embodying the invention;

FIGURE 2 is a transverse fragmentary vertical section thereof takensubstantially along the line 22 of FIG- URE 1;

FIGURE 3 is a fragmentary plan view thereof;

FIGURE 4 is afragmentary longitudinal vertical section thereof takensubstantially along the line" 4-4 of FIGURE 3; and

FIGURE 5 is a schematic diagram illustrating the electrical circuitrythereof.

In the exemplary embodiment of the'invention as disclosed in thedrawings, a chest type freezer generally designated 10 is shown tocomprise a cabinet 11 having a right upper side wall 12, a right lowerside wall 13, a left side wall 14, a rear end wall 15, a front end wall17, an upper bottom wall 18, and a lower bottom wall 19. The side endand bottom walls cooperatively define an upwardly opening spacegenerally designated 20 which is divided into a main storage chamber 21and a smaller sharp-freeze chamber 22, by a pair of upright dividingwalls 23 and 23a housing a conventional evaporator 24. The open top ofthe cabinet may be selectively closed by a conventional lid 25. As shownin FIGURE 1, each of the walls 12-19 is defined by an inner liner 26, anouter member 27, and a body of suitable insulating material 28 betweenthe liner and outer member.

As indicatedrbriefly above, the present invention comprehends a freezerstructure wherein the refrigeration of the space 20 to the desiredsub-freezing temperature is effected without use of the conventionalevaporator structures formerly provided in the outer cabinet walls.Herein the refrigeration of the space 20 is effected solely by theforced circulation of air through the chambers 21 and 22, which air isrefrigerated to a sub-freezing temperature in passing in thermalassociation with the evapo rator 24 in the dividing wall 23. Morespecifically, wall 23 defines a first inlet 29 from chamber 21 to theinterior thereof, and a second inlet 30 from chamber 22 to the interiorthereof. A outlet 31 is provided in the dividing wall 23a adjacent thebottom thereof in communication with a fan chamber 32 defined by anenclosure 33 and housing a fan 34 driven by a suitable electric motor34a.

A plate 35 extending across the fan chamber 32 and '22, and in a secondpath downwardly to an outlet opening 38 at the bottom of chamber 21.

Referring now more specifically to FIGURES 1-3, the refrigerated airdelivered from fan 34 through opening 38 is delivered to chamber 21 byan improved distribution structure generally designated 39 which effectsa substantially uniform distribution of the refrigerated air throughoutchamber 21 thereby effectively refrigerating the chamber uniformly tothe preselected sub-freezing temperature. As shown in FIGURE 3, thedistribution structure 39 includes a first, tubular duct 40 extendingcentrally longitudinally along the bottom wall 19 substantially betweenwalls 13 and 14, a second, upwardly open duct 41 extendinglongitudinally along bottom wall 19 adjacent front Wall 17, and a third,upwardly open duct 42 extending longitudinally along bottom wall 19adjacent rear wall 15. Approximately midway between .walls 13 and 14, afirst, upwardly open interconnecting duct 43 connects duct 40 to duct41, and a second, upwardly open interconnecting duct 44 connects duct 40to duct 42. The left-hand end of each of ducts 40, 41 and 42 opens intoa space 45 adjacent the-left side wall 14 at the bottom of a wire framestructure 46 secured to the wall 14- and defining a vertically extendingair passage 47 for assuring a conduction of a portion of the airdelivered from fan 34 to an upper portion of chamber 21 subjacent lid 25notwithstanding a loaded condition within chamber 21. The refrigeratedair is delivered from duct 40 to ducts 43 and 44 through a pair ofoutlets 48. Thus, low temperature air is delivered through the openducts 41-44 to the chamber 21 adjacent the bottom wall 19 at a pluralityof points assuring a uniform distribution of the refrigerated airthroughout the chamber 21.

Referring now more specifically to FIGURE 2, duct 40 is shown tocomprise a depressed portion 50'of the liner 26a of bottom wall 19, anda flat plate 51 provided with a pair of downturned edge flanges 52 eachhaving an outlet opening 48 for communication between the duct 40 andthe respective interconnecting ducts 43 and 44. As illustrated, theducts 41, 42, 43 and 44 comprise upwardly opening channels in the liner26 depressed below the fiat plane of the liner with which the plate 51is in coplanar association. Thus, as shown in FIGURE 2, the refrigeratedair passing to ducts 41-44 front duct 46 may move upwardly throughchamber 21 from any por-' tion thereof as long as no restriction isplaced on such flow as by the placement of objects (not shown) on thebottom wall 19. Thus, in effect, the ducts 41, 42, 43 and 44 compriseoutlets cooperating with openings 48 to deliver the refrigerated airfrom the duct 40 upwardly adjacent the walls defining the lateralboundaries of the space 21 and eifectively surrounding goods placed inthe chamber 21 with an enclosure of refrigerated air. Further, the plate51 may be formed of a thermally conductive material such as metalwhereby the refrigerated air passing through the duct 40 causes theplate 51 to act 'as a cold plate at the bottom of the chamber 21.

As illustrated in .FIGURE 3, the left-hand end 75 of ducts 41 and 42communicates with duct 4tlthrough space 45. Likewise, the right-hand end76 of ducts 41 and 42 communicates with duct 40 in the vicinity of thelower right side wall 13. Thus, in addition to cold air flowing fromduct 40 into ducts 41 and 42 via openings 48, cold air also enters theseducts 41 and 42 from duct 40 through both the rightahand ends 76 and theleft-hand ends 75. The tendency of the air entering the ducts 41 and 42is to permeateupwardly through the food packages on its way to opening29. Thus by having air enter ducts 41 and 42 at three spaced points,namely 75, 48 and 76, it is assured that a sufficient quantity of air isavailable at all points along the lengths of ducts 41 and 42, andconsequently, a uniform distribution of cold air throughout the chamber21 is provided.

It should be noted that at no time is the passage of air from fan 34completely blocked notwithstanding the relationship with the ducts 41444as the grid structure 46 effectively maintains the passage 47 open toprovide a circulation of the refrigerated air through the upper portionof chamber 21 back through the inlet 29 in wall portion 26b extendsgenerally horizontally from portion 56 to liner portion 37 and definesthe lower end of the dividing walls 23 and 23a. The liner portion 57 isprothe lower end of the liner portion 56 to cooperate with the linerportion 57 in defining a passage for conducting air from opening 36 toopening 56a for delivery through duct '55 to the chamber 22. As shown inFIGURES 3 and 4, the liner portion 26b may be provided with a pluralityof upwardly projecting angular ribs 65 serving to space goods placed inchamber 22 upwardly of the level of the fiat plane of the liner toeffectively preclude blocking of the duct'55 thereby and to also allowair delivered to duct 55 to spread outwardly toward walls 15 and 17whereupon it permeates upwardly through the food packages on its Way toopening 30.

Asshown in FIGURE 1, the refrigerated air delivered to chamber 22 fromduct 55 passes upwardly therethrough and is recirculated back toevaporator 24'through the inlet opening 30 in the dividing'wall 23.Thus, the recirculated air from each of chambers 21 and 22 is mixedwithin the dividing wall 23 at evaporator 24 and recircu- 'lated bymeans of fan 34 to the respective chambers as discussed above.

The operation of freezer 10 is best seen by reference to FIGURES. Motorcompressor 63 is connected from a placement of goods in substantiallycomplete overlying a freezer while yet eliminating the relatively videdwith a melt-collecting depressed portion 58 having an opening 59 throughwhich melt resulting from a defrosting of evaporator 24 may pass to aconduit 60 extending through lower right side wall 13 to a machineryspace 61 below bottom wall 18 for collection in a pan 62. The motorcompressor 63 of the refrigeration apparatus is disposed in space 61directly below pan 62 and the heat thereof is directed upwardly againstthe pan to evaporate the collected melt, thereby dissipating it toatmosphere and eliminating the need for drain connections from thefreezer. As best seen in FIGURE 1, a connecting plate 64 extends betweenliner portion-37 and thermostat switch 66 to a fixed contact 67 of atimer switch 68. The thermostat switch 66 is connected to one powersupply lead L1 and the movable contact 69 of the timer switch 68 isconnected to the other power supply lead L2 so that when the movablecontact 69 engages the fixed contact 67 and the thermostat switch 66 isclosed the motor compressor 63 is connected between the power supplyleads L1 and L2. The motor 70 of timer switch 68 is connected inparallel with motor compressor 63 from thermostat switch 66 to lead L2and thus clocks the accumulated-compressor running time in controllingthe operation of movable switch contact 69. Fan motor 35 is connectedbetween lead L1 and fixed contact 67 of timer switch 68 and movablecontact 69 is normally in .engagement with fixed contact 67 so that fanmotor 35 is normally energized providing the desirable forcedcirculation of the refrigerated air discussed above. However, when timermotor 70 clocks suflicient compressor running time, the movable con-tact69 is switched from fixed contact 67 to a second fixed contact 71 oftimer switch 68 to which is connected a defrost heater 72 in series witha bimetallic control switch 73 for defrosting the evaporator 24 in theconventional manner. As the movable contact 69 is no longer inengagement with contact 67, the compressor 63 and the fan 35 areinoperative during the defrosting operation. I

Thus, applicants refrigeration apparatus as disclosed above provides ahighly desirable frost-free operation of V V costly evaporatorstructures in the cabinet walls. By virtue of the improved uniformdistribution of the refrigerated air in the chambers, improved freezingand storage of goods in the chambers is obtained.

, While I have shown and described one embodiment of my invention, it isto be understood that it is capable of many modifications. Changes,therefore, in the construction and arrangement may be made withoutdeparting from the spirit and scope of the invention as defined in theappended claims.

air under pressure fol-refrigerating said chamber to a subfreezingtemperature; means for delivering refrigerated air from the providingmeans through a plurality of upwardly opening inlets to the chamberadjacent to each of said walls at the bottom of said chamber to define ablanket of cold air surrounding the chamber inwardly of said Walls andthereby refrigerate the chamber substantially uniformly throughout tosaid sub-freezing temperature; and means precluding delivery ofrefrigerated air into said chamber from the bottom of the centralportion of the chamber.

. 2. Refrigeration apparatus, comprising: Wall means defining a chamberand having left and right side walls and front and rear end walls; meansfor providing refrigerated air under pressure for refrigerating saidchamber to a sub-freezing temperature; a first duct extendingsubstantially between said sidewalls at the bottom of said chamber andarranged to receive refrigerated air from said providing means; a secondupwardly opening duct extending horizontally along an end wall at thebottom of the chamber; and means for providing air from said first ductto said second duct to pass into the chamber at substan- I tially spacedpoints therein to refrigerate the chamber substantially uniformlythroughout to said sub-freezing temperature.

3. Refrigeration apparatus comprising: wall means defining a chamberhaving left and right side walls and front and rear end walls; means forproviding refrigerated air 1 under pressure'for refrigerating saidchamber to a subfreezing temperature; a first duct extendingsubstantially chamber at substantially spaced points thereof adjacentunder pressure for refrigerating said chamber to a sub-' freezingtemperature; a first duct extending substantially between said sidewalls at the bottom of said chamber and arranged to receive refrigeratedair from said providing means; a second, upwardly opening duct extendinghorizontally along an end wall at the bottom of the chamber;

between said side walls at the bottom of said chamber and arranged toreceive refrigerated air from said providing means; a second upwardlyopening duct extending horizontally along an end wall at the bottom ofthe chamber; a third upwardly opening duct extending horizontally alongthe other end wall, at the bottom of the chamber; and means forproviding refrigerated air from said first duct to said second and thirdducts to pass into the chamtween said side walls at the bottom of saidchamber and arranged to receive refrigerated air from said deliveringmeans; means for delivering refrigerated air from said duct through aplurality of upwardly opening inlets to the means for providing air fromsaid first duct-to said second duct intermediate the ends thereof; andmeans for delivering refrigerated air from one end of the ducts adjacentone of said side walls to the chamber to refrigerate the chambersubstantially uniformly throughout to said sub-freezing temperature.

References Cited in the file of this patent UNITED STATES PATENTS1,912,688 Bromann June 6, 1933 1,973,022 I Strobell Sept. 11, 19342,074,375 Dick Mar. 13, 1937 2,203,814 Clements June 11, 1940 2,290,647Lowell July 21, 1942 2,337,089 Ellsworth Dec. 21,1943 2,463,104 HenderMar. 1, 1949 2,508,768 Munshower May 23, 1950 2,545,602 Burger Mar. 20,1951 2,553,471 Protzeller May 15, 1951 2,693,089 Teeter Nov. 2, 19542,929,227 Rainwater Mar. 22, 1960 3,056,274 Pouchert Oct. 2, 1962 UNITEDSTATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 137, 146June 16, 1964 Ralph E. Wallenbrock fied that error appears in the abovenumbered pat- It is hereby certi and that the said Letters Patentshouldread as ent requiring correction corrected'belom- Column 2, line 15,after- "side" insert a comma; column 3, line 16, for "front" read fromsi ned and sealed this 5th day of January 1965.

(SEAID Atte'stz EDWARD J. BRENNEE Commissioner of Patent EkN'EsT wiSWIDER Arte/sting Officer

1. REFRIGERATION APPARATUS COMPRISING: WALL MEANS DEFINING A CHAMBERHAVING LEFT AND RIGHT SIDE WALLS AND FRONT AND REAR END WALLS; MEANS FORPROVIDING REFRIGERATED AIR UNDER PRESSURE FOR REFRIGERATING SAID CHAMBERTO A SUBFREEZING TEMPERATURE; MEANS FOR DELIVERING REFRIGERATED AIR FROMTHE PROVIDING MEANS THROUGH A PLURALITY OF UPWARDLY OPENING INLETS TOTHE CHAMBER ADJACENT TO EACH OF SAID WALLS AT THE BOTTOM OF SAID CHAMBERTO DEFINE A BLANKET OF COLD AIR SURROUNDING THE CHAMBER INWARDLY OF SAIDWALLS AND THEREBY REFRIGERATE THE CHAMBER SUBSTANTIALLY UNIFORMLYTHROUGHOUT TO SAID SUB-FREEZING TEMPERATURE; AND MEANS PRECLUDINGDELIVERY OF REFRIGERATED AIR INTO SAID CHAMBER FROM THE BOTTOM OF THECENTRAL PORTION OF THE CHAMBER.